105921-8570 ZEXEL 9 420 610 871 BOSCH GOVERNOR 9420610871 1059218570 1920017d02

Fig. 32-In-Circuit Negative Rectifier Diode Test PointsTo check negative diode assembly, connect tester to diode plate stud (1, Fig. 32) and to diode lead (2). Check remaining diodes (3 and 4) by the same method.
Fig. 33-In-Circuit Positive Rectifier Diode Test PointsTo check positive diode assembly, connect tester to output terminal (1, Fig. 33) and to diode lead (2). Check remaining diodes (3 and 4) by the same method.In-Circuit Rectifier Diode Test With Test Light
IMPORTANT: Do not use a 120-volt test lamp. Use a 12-volt DC test lamp only; otherwise diodes will be damaged.
Fig. 34-In-Circuit Negative Rectifier Diode Test PointsTo check negative diode assembly, connect test lamp probes to diode plate stud (1, Fig. 34) and to diode lead (2). Reverse test lamp probes. Test lamp should light in one direction only.Recheck diodes individually after disassembly to determine which diode is shorted if test lamp lights in both directions.
Fig. 35-In-Circuit Positive Rectified Diode Test PointsTo check positive diode assembly, connect test lamp probes to output terminal (1, Fig. 35) and to diode lead (2). Reverse test lamp probes. Test lamp should light in one direction only.Recheck diodes individually after disassembly to determine which diode is shorted if test lamp lights in both directions.Field Leakage (Short) Test
Remove the regulator and brush assembly.
Fig. 36-Field Leakage Test PointsConnect ohmmeter or test lamp (12 volt or 120 volt may be used) test probes to one of the slip rings (1, Fig. 36) and to the ground terminal (2).Ohmmeter resistance should be infinite (test lamp should not light).Repeat test after rotor has been removed to ascertain leakage or short. Connect test probes to one of the slip rings and to rotor shaft.In-Circuit Stator Leakage (Short) Test
IMPORTANT: Do not use a 120-volt test lamp. Use a 12-volt DC test lamp only, otherwise diodes will be damaged.
Fig. 37-In-Circuit Stator Leakage Test PointsTo check stator leakage, connect test lamp probes to diode plate (1, Fig. 37) and to diode lead 2. Reverse test lamp probes. Test lamp should light in one direction only.Repeat test after stator has been removed if test light lights in both directions.Out-of-Circuit Stator Leakage (Short) Test
Remove rectifier diode plates and stator as an assembly.
Fig. 38-Out-of-Circuit Stator Leakage Test PointsConnect ohmmeter or test lamp (12 volt only) probes to a diode lead (1, Fig. 38) and to the stator (2).Resistance reading should be infinite (test lamp should not light).Stator
Disconnect the stator leads from the diode leads.
Fig. 39-Grounded Stator Winding Test PointsCheck for a grounded winding by connecting ohmmeter probes to one stator lead (1, Fig. 39) and to the stator frame (2). The ohmmeter reading should be infinite.
Fig. 40-Shorted Stator Winding Test PointsUsing a sensitive ohmmeter which has been carefully zeroed, connect probes to lead (1, Fig. 40) and to lead (2). Resistance should be 0.4 ohm. If the reading is infinite replace stator.With the ohmmeter probes on (1) and (2) touch leads (3) and (4) together. Resistance should be 0 ohm. If resistance is not 0 ohm, replace stator.Repeat test on leads (1)